A vehicle such as an automobile is provided with a vehicle-cabin front interior panel called an instrument panel or a dashboard or the like, in a vehicle cabin at its front portion.
Some of such vehicle-cabin front interior panels have a multilayer structure formed of a cushion layer and a soft and thin skin material laminated on a surface of a hard core material.
The soft and thin skin material is typically manufactured by powder slush molding, vacuum molding, or the like.
Among these moldings, the powder slush molding, in short, involves melting and adhering resin powder to a heated mold thereby to perform molding, and the vacuum molding, in short, involves bringing a thermally softened thermoplastic resin sheet into intimate contact with a vacuum mold by vacuum suction thereby to form the thermoplastic resin sheet into the shape of the vehicle-cabin front interior panel.
Since such powder slush molding or vacuum molding uses particular facilities, development of a technology for enabling injection molding using general facilities to mold the soft and thin skin material has advanced. (Refer to Patent Literature 1, for example.)